.travis.yml: Test click 5.1

Author: jayvdb

.travis.yml

@@ -22,6 +22,8 @@ script:
  - py.test tests --cov click_aliases --cov-report term-missing
  - pip install 'click>6,<7'
  - py.test tests --cov click_aliases --cov-report term-missing --cov-append
+ - pip install 'click>5,<6'
+ - py.test tests --cov click_aliases --cov-report term-missing --cov-append
 
 after_success:
  - coveralls